1. Field of the Invention
The present invention relates to a method of spinal fixation involving application of a liquid medium which cures, hardens, polymerizes or otherwise serves to bind adjacent vertebrae together. The fixation which results from this binding may be temporary or essentially permanent in duration.
2. Description of the Related Art
The spinal vertebrae are separated by cartilage disks, filled with a gelatinous substance, that provide cushioning to the spinal column. These disks may herniate or rupture from trauma or strain, especially if degenerative changes have occurred in the disk.
A herniated intervertebral disk, also known as a slipped or ruptured disk, is a condition in which part or all of the soft, gelatinous nucleus pulposus in the central portion of an intervertebral disk is forced through a weakened part of the annulus fibrosis, resulting in back pain and nerve root irritation.
Most herniation takes place in the lumbar area of the spine. Lumbar disk herniation occurs 15 times more often than cervical disk herniation, and it is one of the most common causes of lower back pain. The cervical disks are affected 8% of the time and the thoracic disks only 1 to 2% of the time. When lumbar disk herniation occurs, nerve roots, the large nerves that branch out from the spinal cord, may become compressed resulting in neurological symptoms such as pain or weakness in the back and lower extremities.
Although minor cases of disk herniation may be treated with bed rest and medications to relieve pain and reduce inflammation, surgery may be indicated for people who fail to respond to bed rest and medications.
One common type of surgery performed to alleviate back pain is discectomy. Discectomy involves the surgical removal of the diseased disc, thereby relieving the pressure. In spite of the fact that the procedure has been done for many years, few studies have been conducted to determine its real effectiveness. Scar tissue may develop after discectomy, which, in some cases, can cause continued pain.
Another common procedure is spinal fusion. Spinal fusion involves making a percutaneous incision or puncture over the affected area of the spine and joining the vertebrae together using bone grafts and/or rods made of metal or other materials of substantial strength.
Another procedure performed is laminectomy. Laminectomy is performed to remove the protruding disk. This procedure involves removing the bone that curves around and covers the spinal cord (lamina) and the tissue that is causing pressure on the nerve or spinal cord.
Complications of spinal surgery can include nerve and muscle damage, infection, scarring, and the need for re-operation. Patients often remain hospitalized for several days after surgery, and in bed for anywhere from a few days to a few weeks following surgery. A back brace or cast may be necessary for weeks following the surgery to immobilize the spine until the fusion has occurred.